Reported Reactions

Drugs

Brand name · Cannabidiol

Epidiolex: adverse event reports filed with FDA

17,803 reports list it as a suspect or interacting product, 2017–2026. Also reported as Epidiolex Oral Soln.

17,803
reports as suspect product
0.1% of all reports · about 1,998 a year
1,227
reports, 12 months to June 2026
1,522 in the 12 months before
54%
marked serious by the reporter
57.4% across all reports
8.8%
record death among outcomes, as reported
1,561 reports · not verified by FDA

17,803 adverse event reports received by FDA list the brand name Epidiolex (cannabidiol) as a suspect or interacting product, from August 2017 to June 2026. A further 1,656 reports list it only as a concomitant medication, and those are not counted in the figures on this page.

In the 12 months to June 2026, 1,227 reports listed it, down 19% from 1,522 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 1,998 reports a year and 0.1% of the 20,646,523 reports in the database. How many people take it is not in the data, so a count is not a rate of occurrence.

The reactions recorded most often are seizure (28%), hospitalisation (13.2%) and off label use (9%). A report can list several reactions, so shares add to more than 100%; 786 different terms appear across these reports. Seizure is recorded in 28% of these reports, against 0.5% of all reports in the database.

54% of the reports are marked serious by the reporter; 8.8% record death among the outcomes and 31.1% record hospitalisation, as reported. 53.1% of the reports came from consumers, and the largest patient age group is 18 to 44 (6%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

0447894Jul 2021: 292Aug 2021: 249Sep 2021: 292Oct 2021: 310Nov 2021: 315Dec 2021: 3412022Jan 2022: 276Feb 2022: 277Mar 2022: 344Apr 2022: 180May 2022: 139Jun 2022: 156Jul 2022: 894Aug 2022: 136Sep 2022: 126Oct 2022: 122Nov 2022: 140Dec 2022: 1112023Jan 2023: 108Feb 2023: 101Mar 2023: 101Apr 2023: 78May 2023: 98Jun 2023: 624Jul 2023: 69Aug 2023: 147Sep 2023: 87Oct 2023: 97Nov 2023: 98Dec 2023: 1022024Jan 2024: 123Feb 2024: 98Mar 2024: 91Apr 2024: 115May 2024: 117Jun 2024: 107Jul 2024: 210Aug 2024: 107Sep 2024: 92Oct 2024: 140Nov 2024: 97Dec 2024: 1012025Jan 2025: 127Feb 2025: 126Mar 2025: 135Apr 2025: 138May 2025: 135Jun 2025: 114Jul 2025: 111Aug 2025: 85Sep 2025: 113Oct 2025: 94Nov 2025: 84Dec 2025: 952026Jan 2026: 108Feb 2026: 90Mar 2026: 120Apr 2026: 113May 2026: 102Jun 2026: 112

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

01,8243,6472017: 1620172018: 6920182019: 3,07820192020: 2,98220202021: 3,64720212022: 2,90120222023: 1,71020232024: 1,39820242025: 1,35720252026: 6452026

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Epidiolex reports recording the termall reports in the database

  1. Seizurea fit or convulsion28%4,986
  2. Hospitalisationadmission to hospital13.2%2,353
  3. Off label useused for a purpose or in a way not on the label9%1,607
  4. Product use in unapproved indicationused for a purpose not on the label8.8%1,564
  5. Diarrhoealoose or frequent stools7.3%1,297
  6. Deaththe patient died; cause not stated by this term7%1,238
  7. Somnolencedrowsiness5.2%926
  8. Product dose omission issuea dose was missed5.1%909
  9. Weight increasedweight gain3.7%667
  10. Fatiguetiredness3.7%651
  11. Drug ineffectivethe medicine did not work as expected3.5%632
  12. Weight decreasedweight loss3.5%628
  13. Vomitingbeing sick2.6%471
  14. Decreased appetitereduced appetite2.6%463
  15. Condition aggravatedthe condition being treated got worse2.3%411
  16. Pneumonialung infection2.3%406
  17. Emergency care1.7%303
  18. Aggressionaggressive behaviour1.7%301
  19. Falla fall1.7%300
  20. Insomniadifficulty sleeping1.7%300
  21. Product dose omissiona dose was missed1.7%297
  22. Nauseafeeling sick1.6%288
  23. Lethargysluggishness1.4%251
  24. Drug interactionan interaction between medicines1.3%233
  25. Constipationconstipation1.3%223
  26. Rashskin rash1.2%217
  27. Pyrexiafever1.2%210

Top 30 of 786 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the share of all reports in the database; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Death8.8%1,561
Life-threatening0.4%67
Hospitalisation (initial or prolonged)31.1%5,544
Disability0.2%35
Congenital anomaly0%8
Other serious26.7%4,752
Not serious46%8,182

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 20,646,523 reports. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 20.5%84
2 to 115.4%958
12 to 173%535
18 to 446%1,077
45 to 641.3%233
65 to 740.3%47
75 and over0.1%16
Age not given83.4%14,853

Patient sex

Female19.4%3,448
Male23.9%4,262
Not given56.7%10,093

Who reported

Physician19.9%3,544
Pharmacist2.2%394
Other health professional24.5%4,359
Lawyer0%0
Consumer or non-health professional53.1%9,456
Not given0.3%50

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 96.6% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Lennox-gastaut syndrome6,48636.4%
Epilepsy3,93422.1%
Seizure9715.5%
Partial seizures9515.3%
Idiopathic generalised epilepsy5843.3%
Severe myoclonic epilepsy of infancy3672.1%

The indication field is filled in by the reporter and is often blank; shares are of all 17,803 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Epidiolex reports
Clobazam1,5608.8%
Onfi1,5368.6%
Keppra1,2827.2%
Vimpat1,0325.8%
Clonazepam1,0185.7%
Levetiracetam7324.1%
Lamotrigine7104%
Depakote6603.7%
Diazepam5943.3%
Lamictal5583.1%

Other products listed in reports where Epidiolex is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasureEpidiolexAll reports
Reports as suspect product17,80320,646,523
Share of that pool—0.1%
Reports, latest 12 months1,2271,332,454
Marked serious54%57.4%
Death recorded among outcomes, per 1,000 reports8891
Hospitalisation recorded, per 1,000 reports311213
Consumer-filed share53.1%45.8%
Top term, share of reportsSeizure 28%0.5%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Questions about Epidiolex reports

How many adverse event reports has FDA received for Epidiolex?

17,803 reports list Epidiolex as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 1,227 of them arrived in the latest 12 months. Another 1,656 list it only as a concomitant medication.

What reactions are recorded in Epidiolex reports?

seizure (28%), hospitalisation (13.2%), off label use (9%), product use in unapproved indication (8.8%) and diarrhoea (7.3%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Epidiolex was responsible.

How serious are the reports?

54% are marked serious by the reporter. Among the outcomes recorded, 8.8% of reports include death and 31.1% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

consumer or non-health professional (53.1%), other health professional (24.5%) and physician (19.9%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Epidiolex rising?

1,227 reports in the 12 months to June 2026, down 19% from 1,522 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Epidiolex was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Epidiolex?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Epidiolex as a suspect or interacting product; reports listing it only as a concomitant medication (1,656) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.